Portland UG Network Willamette River Crossing
Michels completed two parallel horizontal directional drills (HDD-1 and HDD-2) beneath the Willamette River in Portland, OR. As part of the EPA Harbor Superfund Mile 11 Cleanup initiative, we installed carrier pipe for housing conduit to replace electric circuits originally laid on the riverbed.
The alignment required vertical and horizontal curves. Drills reached a depth of 253 feet below the river water level, 330 ft below the entry point.
Two 60-inch steel casings (160 linear feet each) were installed via pneumatic pipe ramming on the west side to isolate the contamination layer, followed by 48-in casings installed using retractable Direct Pipe® to reach the consolidated Troutdale layer.
On the east side, 42-in steel casings (160 LF each) were installed to reach the Troutdale layer. Drill rigs were then set up on both sides; survey guidance was used for an intersect. After intersecting, 600 LF segments of 24-in pipe were staged in city streets and pulled back while suspended 30 ft in the air. The final lengths were 3,006 LF (HDD-1) and 3,065 LF (HDD-2).
Through the EPC delivery method, the Michels team developed an innovative, cost-effective, and constructable solution that improved previous design iterations involving high costs and/or constructability concerns due to the unique challenges of the subsurface geology common in the region.
The design intentionally placed the directional drills closer than normal HDD standards. Industry norms call for parallel drills spaced 15 ft apart. This project required “stacking” the drills on the east side and spacing them only 5 ft apart on the west side.
Michels’ work on this project earned an Engineering News-Record Regional Best Project Award and runner-up in Trenchless Technology’s Project of the Year Awards in 2025.
